USA300 methicillin-resistant S. aureus (USA300 MRSA) colonization and the risk of MRSA infection in residents of extended-care facilities.

To examine the pathogenesis of USA300 MRSA infection in long-term care residents, we performed a retrospective cohort study of 1691 adult residents of two extended-care facilities from 2003 to 2007 to assess whether the risk of subsequent MRSA infection is higher in USA300 MRSA-colonized residents compared to non-colonized residents or non-USA300 MRSA colonized residents. Six per cent of residents were colonized with USA300 MRSA; 12% of residents were colonized with non-USA300 MRSA; and 101 residents developed MRSA infection. The risk of infection was twofold higher in residents colonized with USA300 MRSA compared to residents not colonized with MRSA [adjusted hazard ratio 2·3, 95% confidence interval (CI) 1·1-4·5]. The risk of infection in USA300 MRSA-colonized residents was similar to USA300 MRSA non-colonized residents (relative risk 1·1, 95% CI 0·5-2·3). Our findings show that colonization with USA300 MRSA increases the risk of MRSA infection suggesting a similar pathogenesis.

Comparison of culture media for detection of Acinetobacter baumannii in surveillance cultures of critically-ill patients.

The objective of this study was to evaluate the performance of CHROMagar Acinetobacter when compared to sheep blood agar, MacConkey agar and MacConkey agar with 6 µg/ml of imipenem for the detection of A. baumannii in surveillance cultures of hospitalized patients. We utilized peri-anal swabs and sputum samples from patients admitted to the University of Maryland Medical Center ICUs from December 7 through December 21, 2009. Samples were plated onto four media in the following order: (1) 5% sheep blood agar (SBA), (2) MacConkey agar, (3) MacConkey agar with 6 µg/ml of imipenem, and (4) CHROMagar Acinetobacter (CHROMagar). SBA was the gold standard to which all media was compared. There were 165 samples collected during the study period. SBA and CHROMagar detected 18 of 18 (100%) Acinetobacter and 11 of 11 (100%) MDR-A. baumannii. MacConkey agar detected 16 of 18 (89%) Acinetobacter and 10 of 11 (91%) MDR- A. baumannii while MacConkey agar with 6 µg/ml imipenem detected 9 of 11 (82%) MDR-A. baumannii. CHROMagar did not differentiate MDR- A. baumannii from non-MDR-A. baumannii. CHROMagar may be useful for rapid detection of patients with MDR-A. baumannii if improved upon to better select for MDR-A. baumannii.

Update on resistance of Bacteroides fragilis group and related species with special attention to carbapenems 2006-2009.

The susceptibility trends for the species of the Bacteroides fragilis group against various antibiotics were determined using data from 4 years [2006-2009] on 1957 isolates referred by 8 medical centers participating in a National Survey for the Susceptibility of B. fragilis. The antibiotic test panel included doripenem, ertapenem, imipenem, meropenem, ampicillin:sulbactam, piperacillin:tazobactam, cefoxitin, clindamycin, moxifloxacin, tigecycline, chloramphenicol and metronidazole. MICs were determined using agar dilution methods following CLSI recommendations. Genetic analysis of isolates from 2008 with elevated MICs (>2 µg/mL) to one or more of the carbapenems to detect presence of the cfiA gene was performed using PCR methodology. The results showed an increase in the resistance rates to the ß-lactam antibiotics. High resistance rates were seen for clindamycin and moxifloxacin (as high as 60% for clindamycin and >80% for moxifloxacin), with relatively stable low resistance (5.4%) for tigecycline. For carbapenems, resistance in B. fragilis was 1.1%-2.5% in 2008-9. One isolate resistant to metronidazole (MIC 32 µg/mL) was observed as well as isolates with elevated MICs to chloramphenicol (16 µg/mL). Genetic analysis indicated that the cfiA gene was present in some but not all of the isolates with high MICs to the carbapenems. These data indicate that there continue to be changes in susceptibility over time, and that resistance can be seen among the carbapenems. High antibiotic resistance rates tend to be associated with specific species.

Bladder endometriosis: laparoscopic treatment and follow-up.

OBJECTIVES: This study aims to show the treatment outcome in women affected by isolated bladder endometriosis who underwent laparoscopic surgery in our units. Only women with deep nodules located in the bladder were selected, thus excluding women with deep lesions located in other sites. STUDY DESIGN: Between March 2005 and 2007, women with deep vesical endometriosis, referring to the Departments of Obstetrics and Gynaecology of University Hospitals "G. Martino"of Messina, "Paolo Giaccone"of Palermo and "San Paolo"of Milano, were respectively recruited. A preoperative assessment of the pathology was performed. Women who were concomitantly diagnosed deep nodules of the rectovaginal septum and/or endometriotic ovarian cysts were excluded. A medical therapy with oral contraceptive and/or GnRH analogues was first proposed to the patients affected. If medical treatment failed, a laparoscopic treatment was suggested. We performed a segmental resection of the involved wall or an extramucosal dissection of the bladder according to the cases. A clinical and an instrumental evaluation by ultrasound was performed every 6 months after surgery for the first year and subsequently every 12 months. At the time of referral, patients were also questioned about any recurrence of symptoms. RESULTS: Eight women, with a mean age of 33.8 (range 30-37 years; S.D.=2.5) and a mean parity of 1 (range 0-2) were recruited. Medical therapy failed in all cases and the women underwent laparoscopic treatment. Surgery was complete in all cases without a need for ureteral cannulation. No intraoperative complications occurred. The mean estimated blood loss was 98 ml (range 40-200 ml). All patients underwent at least the first follow-up assessment. In none of the women, recurrence of bladder endometriotic nodules was documented. In contrast, urinary symptoms were reported in three cases. Nevertheless, all the patients reported improvement of symptoms and declared to be satisfied. CONCLUSIONS: We recommend surgical eradication of bladder lesions. Laparoscopic treatment, in the hands of an expert surgeon, is the management of choice. It offers the best approach to the diagnosis allowing good long-term results, with a less invasive approach. Large multicentric studies are however required prior to drawing definite conclusions.

Meningitis in an adult caused by Hemophilus influenzae, biotype III.

An elderly woman had an abrupt onset of symptoms consistent with bacterial meningitis without an obvious source of infection. The organism, isolated from the blood and CSF, was a nonserotypeable Hemophilus influenzae, biotype III. To our knowledge, this is the first reported case of meningitis caused by this organism.

National survey on the susceptibility of Bacteroides Fragilis Group: report and analysis of trends for 1997-2000.

The results of a multicenter US survey using the National Committee for Clinical Laboratory Standards currently recommended methodology for measuring in vitro susceptibility of 2673 isolates of Bacteroides fragilis group species were compared from 1997 to 2000. The test panel consisted of 14 antibiotics: 3 carbapenems, 3 beta-lactam-beta-lactamase inhibitors, 3 cephamycins, 2 fluoroquinolones, clindamycin, chloramphenicol, and metronidazole. Declines in the geometric mean minimum inhibitory concentrations were seen with imipenem, meropenem, ampicillin-sulbactam, and the cephamycins. Increased geometric means were observed with the fluoroquinolones and were usually accompanied by an increase in resistance rates. Bacteroides distasonis shows the highest resistance rates among beta-lactam antibiotics, whereas Bacteroides vulgatus shows the highest resistance levels among fluoroquinolones. B. fragilis shows the lowest resistance rates for all antibiotics. All strains were susceptible to chloramphenicol and metronidazole concentrations <8 microgram/mL. The data underscore the need for species identification and continued surveillance to monitor resistance patterns.

Prediction of serum vancomycin concentrations following intraperitoneal loading doses in continuous ambulatory peritoneal dialysis patients with peritonitis.

The pharmacokinetics of vancomycin were studied in continuous ambulatory peritoneal dialysis patients with peritonitis. Six patients received an intraperitoneal loading dose of 15 mg/kg and 4 received an intraperitoneal dose of 25 mg/L. The ability of 2 methods to predict serum concentrations during the loading dose exchange was determined. The mean serum concentration after the exchange was 17.8 +/- 2.2 mg/L in patients receiving the loading dose. The mean dialysis clearance in all patients was 0.94 +/- 0.34 L/h. 66.6 +/- 13.4% of a dose was absorbed into the circulation in 4 h. The volume of distribution was 0.61 +/- 0.46 L/kg, and the half-life for equilibration of vancomycin into the circulation from dialysate was 2.76 +/- 0.94 h. Two methods of predicting serum vancomycin concentrations were tested, with 1 method predicting values significantly different from measured concentrations while the other did not. Serum vancomycin concentrations can be accurately predicted during a loading dose exchange.

The impact of an enteroviral RT-PCR assay on the diagnosis of aseptic meningitis and patient management.

BACKGROUND: Enterovirus (EV) is a major cause of aseptic meningitis and non-specific febrile illness in children. Since the majority of patients are hospitalized for possible bacterial infection, a rapid test for the diagnosis of enteroviral meningitis (EVM) may reduce hospitalizations and unnecessary treatments. OBJECTIVE: To review the impact of an EV reverse transcriptase-polymerase chain reaction (RT-PCR) assay for the diagnosis of EVM on patient management. STUDY DESIGN: CSF from 1056 patients admitted to the hospital between 1998 and 2001 was tested using EV RT-PCR. The results were correlated with CSF counts, diagnosis, test turnaround time (TAT) and length of hospital stay (LOS). RESULTS: EV RT-PCR was positive for 113 patients (11%). Of these cases, 92% occurred during the summer months and 77% were in children <19 years of age. Children <3 years old with EVM frequently had non-specific clinical findings and lacked pleocytosis. There was a significant correlation between decreasing LOS and TAT (r(2)=0.97, P<0.001). CONCLUSION: RT-PCR testing for EVM is an important tool to aid in the diagnosis of children with non-specific febrile illness. This test impacted patient management as measured by shortened patient stays, which should translate into significant health care savings.

A one-step RT-PCR assay using an enzyme-linked detection system for the diagnosis of enterovirus meningitis.

BACKGROUND: Enteroviruses are the most common cause of meningitis in the United States, with an estimated 50000-75000 cases each year. Enteroviral meningitis (EVM) is frequently a diagnosis of exclusion, as viral cultures lack sensitivity and require prolonged incubation periods. OBJECTIVE: To develop a sensitive and rapid test for the diagnosis of EVM. STUDY DESIGN: A rapid, one-step, reverse transcriptase-polymerase chain reaction (RT-PCR) was used in a prospective analysis of 160 patients who had cerebrospinal fluid (CSF) tested for enterovirus. RESULTS: Of the 160 patients, 14 were excluded due to missing CSF viral culture data. A total of 14 were CSF culture positive (10 with pleocytosis) and 19 were PCR positive (15 with pleocytosis). The ability to detect enterovirus by either culture or PCR correlated significantly with the white blood cell count in the CSF (P=0.001). Based on a clinical definition of enterovirus culture positive and pleocylosis: ten had definite EVM and 12 had probable EVM (pleocytosis without any other cause). Four had possible EVM (CSF culture positive without pleocytosis) and 18 had pleocytosis due to other causes. PCR was positive in all ten patients with definite EVM. Five out of 12 patients with probable EVM and three out of four patients with possible EVM. No patients with pleocytosis due to other causes were PCR positive and one patient that was defined as EVM negative (culture negative and no pleocytosis) was PCR positive. Overall, PCR was positive in 18 out of the 26 patients with a likelihood of EVM, while CSF culture was positive in only 14 cases. Our results demonstrated that RT-PCR enhances the sensitivity of enterovirus detection in CSF (69 vs. 54% for culture). CONCLUSION: The diagnosis of EVM is difficult to make clinically: the enhanced sensitivity and rapid turn around time of PCR will be of great clinical benefit.

Undetected vancomycin-resistant Enterococcus in surgical intensive care unit patients.

The rates of vancomycin-resistant Enterococcus (VRE) in a high-risk population were investigated prospectively using an active surveillance method. The costs of conducting active surveillance were calculated. Among the 10 patients found to have VRE, routine cultures identified 3 (30%); thus, 70% of the VRE-colonized patients would have gone undetected in the absence of active surveillance. The total cost for 5 weeks of active surveillance was $2,234. Although active surveillance identified a high rate of VRE-colonized patients who otherwise may not have been identified, it remains to be determined if the additional costs are justified and result in reduced transmission.

Long-term control of Legionella species in potable water after a nosocomial legionellosis outbreak in an intensive care unit.

Environmental and patient-care control measures were initiated in response to an outbreak of legionellosis in an intensive care unit in 1992. The measures included maintaining elevated potable hot-water temperatures following superheating and using sterile water for administrations through nasogastric tubes. Legionella species remained below detectable levels in the potable hot-water system upon reevaluation in 1999. Nosocomial cases of legionellosis have not been reported since the outbreak.

Risk factors for surgical-site infections following cesarean section.

OBJECTIVE: To identify risk factors associated with surgical-site infections (SSIs) following cesarean sections. DESIGN: Prospective cohort study. SETTING: High-risk obstetrics and neonatal tertiary-care center in upstate New York. PATIENTS: Population-based sample of 765 patients who underwent cesarean sections at our facility during 6-month periods each year from 1996 through 1998. METHODS: Prospective surgical-site surveillance was conducted using methodology of the National Nosocomial Infections Surveillance System. Infections were identified during admission, within 30 days following the cesarean section, by readmission to the hospital or by a postdischarge survey. RESULTS: Multiple logistic-regression analysis identified four factors independently associated with an increased risk of SSI following cesarean section: absence of antibiotic prophylaxis (odds ratio [OR], 2.63; 95% confidence interval [CI95], 1.50-4.6; P=.008); surgery time (OR, 1.01; CI95, 1.00-1.02; P=.04); <7 prenatal visits (OR, 3.99; CI95, 1.74-9.15; P=.001); and hours of ruptured membranes (OR, 1.02; CI95, 1.01-1.03; P=.04). Patients given antibiotic prophylaxis had significantly lower infection rates than patients who did not receive antibiotic prophylaxis (P=02), whether or not active labor or ruptured membranes were present. CONCLUSION: Among the variables identified as risk factors for SSI, only two have the possibility to be changed through interventions. Antibiotic prophylaxis would benefit all cesarean patients regardless of active labor or ruptured membranes and would decrease morbidity and length of stay. Women's healthcare professionals also must continue to encourage pregnant women to start prenatal visits early in the pregnancy and to maintain scheduled visits throughout the pregnancy to prevent perinatal complications, including postoperative infection.

Investigation of an outbreak of methicillin-resistant Staphylococcus aureus in patients with skin disease using DNA restriction patterns.

OBJECTIVE: To investigate an outbreak of methicillin-resistant Staphylococcus aureus (MRSA) among patients using chromosomal typing of the isolates. DESIGN: Comparison of epidemiological and clinical data to endonuclease restriction fragmentation analysis (RFA) of the MRSA isolates associated with an outbreak. Total DNA from the MRSA isolates was restricted with HINDIII and HAEIII for typing. SETTING: Tertiary care academic medical center. METHODS: An epidemiological investigation of an outbreak of MRSA among patients in private rooms was evaluated by routine infection control methods. The MRSA isolates from blood cultures of 7 patients and the nares of a nurse were collected during the outbreak. MRSA isolates from 23 patients not associated with the outbreak also were collected. The total DNA of the MRSA isolates were restricted with HINDIII and HAEIII and electrophoresed on 0.6% agarose gels. RESULTS: MRSA from 4 of the 7 bacteremic patients and the nurse on the outbreak unit had the same endonuclease restriction pattern. The patients were linked in that they were compromised by severe psoriasis or skin ulcers, were on the unit during the same period, and had oatmeal baths in a common bathtub. Of 50 staff members screened, the nurse was the only person detected as colonized by the strain. The other 3 patients on the unit as well as the 23 patients in other locations not associated with the outbreak had MRSA isolates with different RFA patterns. The use of the bathtub was discontinued and further transmission of MRSA was stopped. CONCLUSIONS: A comparison of the relatedness of MRSA by RFA demonstrated the uniqueness of the epidemiologically linked isolates and the utility of the RFA technique in the performance of routine infection control investigations.

Relatedness of coagulase-negative staphylococci causing bacteremia in low-birthweight infants.

OBJECTIVE: To investigate coagulase-negative staphylococcus (CONS) causing bacteremia in a neonatal intensive care unit (NICU). DESIGN: A 14-month retrospective review of 47 infants in the NICU with CONS bacteremia was undertaken to determine CONS glycocalyx production, plasmid pattern, total DNA restriction fragment polymorphism, and clinical risk factors. RESULTS: The isolates included 32 Staphylococcus epidermidis, six Staphylococcus haemolyticus, four Staphylococcus warneri, four Staphylococcus saprophyticus, and one Staphylococcus hominis. Sixty-five percent of S epidermidis produced glycocalyx; other species did not. Oxacillin resistance (52%) and the antibiograms of the CONS were consistent with other units in the hospital. Five similar CONS plasmid patterns were found among 16 isolates; 31 isolates had unique patterns. Extractions of total DNA from these isolates were digested using HindIII, HaeIII, and BstEII. Those with similar restriction fragment length patterns could not linked as nosocomially transmitted among infants with bacteremia. CONCLUSION: Our observations suggest that multiple strains of CONS infect infants in the NICU who have similar risk factors. Although current infection control practices limit transmission of a pathogen, they do not prevent CONS bacteremias.

Nosocomial legionellosis associated with aspiration of nasogastric feedings diluted in tap water.

PROBLEM: Two cases of nosocomial legionellosis due to Legionella pneumophila serogroup 6 (Lp6) were identified in the intensive care unit. Both patients had a history of aspiration of nasogastric tube feedings, developed pulmonary infiltrates, had positive cultures for Lp6, had serological titer rises to Legionella, were treated, and recovered. METHOD: Isolates of Lp6 from the potable water system and patients were characterized by DNA restriction enzyme analyses using pulsed-field gel electrophoresis (PFGE). RESULTS: Water samples grew > 10(4) CFU/L of Lp6, and the same PFGE pattern was observed with the patient and water isolates. Potable water was used only for delivering medications and diluting feeding solutions given through the nasogastric tubes of the patients. Heat shock of the hot water system (140 degrees to 160 degrees F or 60 degrees to 70 degrees C, 4 hours) was performed and the temperature was maintained between 131 degrees to 140 degrees F (55 degrees to 60 degrees C). Surveillance over 18 months revealed a reduction in Legionella to < 10(2) CFU/L. CONCLUSION: We speculate that nosocomial Legionella pneumonia occurred due to aspiration of nasogastric tube solutions diluted with tap water. A nursing practice change to use only sterile water to dilute feedings and flush medications for nasogastric administration was instituted. The hot water temperature at the faucet was increased to > or = 131 degrees F (> or = 60 degrees C) to control Legionella. No further nosocomial cases have occurred.

The prevalence survey as an infection surveillance method in an acute and long-term care institution.

A point prevalence survey of infections was done in 22 patients areas at the Albany VA Medical Center between September 17 and 28, 1979. The study was designed by a consultant epidemiologist, two infectious disease physicians, a biostatistician, two infection control nurses, a microbiologist, and a clinical pharmacist. A 16-page worksheet was designed for rapid and complete data collection, with computer codes and programming cross references incorporated. A total of 572 patients were seen and evaluated for signs and symptoms of infection; cultures were taken if indicated, and charts were reviewed. Urine cultures were obtained in 95% of patients. Data available for analysis will allow for a description of the characteristics of the patient population, identification of the most prevalent sites of infection and causative organisms, an analysis of antimicrobial agent use, and a description of the risk factors and their interactions that may influence the acquisition of infection.

Vancomycin assay performance in patients with acute renal failure.

OBJECTIVE: Fluorescence polarization immunoassays (FPIA) have been reported to overestimate vancomycin serum concentrations compared to high-performance liquid chromatography (HPLC) or enzyme multiplied immunoassay technique (EMIT) in patients with chronic renal disease. The assay manufacturer has modified the FPIA to remedy this overestimation. The purpose of this study was to compare the assay performance of two FPIAs to EMIT in acute renal failure patients receiving vancomycin and continuous venovenous hemofiltration. DESIGN: Open-label trial. SETTING: Intensive care unit in a university affiliated hospital. PATIENTS AND PARTICIPANTS: 15 serum and ultrafiltrate samples were obtained from 14 critically ill patients (mean +/- SD; 57 +/- 12 years; 8 males/6 females). MEASUREMENTS AND RESULTS: Vancomycin concentrations were determined by a polyclonal FPIA (pFPIA) performed on the TDx system, a monoclonal FPIA (mFPIA) performed on the AxSYM system and EMIT. The coefficient of variation for all assays was < 5%. The mean difference +/- SDd between mFPIA vs EMIT and pFPIA vs EMIT assays in serum were: -0.08 +/- 1.55 and 1.24 +/- 2.11 mg/l, respectively. The limits of agreement between the mFPIA vs EMIT and pFPIA vs EMIT assays in serum were: -3.18 to 3.03 and -2.99 to 5.46 mg/l, respectively. CONCLUSIONS: Our data demonstrate that the manufacturer's changes to the pFPIA have reduced overestimation. The mFPIA appears to be an acceptable assay for measuring vancomycin serum concentrations in acute renal failure patients and does not significantly overestimate these concentrations.

Laparoscopic-ultrasonographic combined technique for the creation of a neovagina in Mayer-Rokitansky-Kuster-Hauser syndrome.

OBJECTIVE: To create a neovagina using a combined laparoscopic and ultrasonographic technique in Mayer-Rokitansky-Kuster-Hauser syndrome by modification of Vecchietti's operation. DESIGN: Case report. SETTING: Division of Physiopathology of Reproduction, University of Palermo, Palermo, Italy. MAIN OUTCOME MEASURE(S): The advancement of the needle from the pseudohymen, through the vesicorectal space using a triple contrast ultrasonographic technique. RESULT(S): The ultrasonographic scanning guides the accurate transit from external genitalia to the peritoneal cavity. CONCLUSION(S): This original approach allowed a safe and rapid creation of a neovagina in a case of Mayer-Rokitansky-Kuster-Hauser syndrome.

Initial experience of a new linear everting falloposcopy system in comparison with hysterosalpingography.

OBJECTIVE: To assess the endolumenal portion of the fallopian tube from ostium to fimbria using a specially designed linear everting catheter and microendoscope. The study compared falloposcopy results with those obtained with hysterosalpingography (HSG) in the same patients and explored the system's ability to classify internal tubal conditions. DESIGN: A prospective study of a new diagnostic technique, falloposcopy, versus conventional means of evaluating tubal status. SETTING: A tertiary university infertility center. PATIENTS: Eighteen infertile patients with a previous history of infertility of at least 2 years duration. INTERVENTION: Diagnostic falloposcopy was performed on a total of 31 tubes. RESULTS: Although the results of HSG and falloposcopy were in agreement in 19 cases, falloposcopy findings were at significant variance with HSG in 12 cases (40%). Seventeen of the tubes visualized by falloposcopy were considered to be normal, 10 showed mild disease, and 4 were severely damaged. CONCLUSION: Falloposcopy using the linear everting catheter is rapid and atraumatic. It provides more complete information concerning tubal status than HSG and as such constitutes an important advance in diagnosis and therapy planning.

[Fast and accurate method for theophylline analysis in preterm babies using gas chromatography and nitrogen selective detector (NFID) (author's transl)]. / Méthode de chromatographie en phase gazeuse-NFID pour la détermination rapide de la théophylline sanguine chez les enfants prématures.

The combined utilization of (a) a weak polar OV-1 phase, (b) an on-column methylation using a methylating agent commercially available, (c) a nitrogen selective detector (NFID) and (d) a small volume of sample, allows the development of a fast (less than 20 min) and accurate method for theophylline analysis in preterm babies. With 50 microliter of capillary whole blood sample, its limit of sensitivity was 0.5 microgram/ml of theophylline. This method is most desirable for theophylline monitoring in treating apnea of premature infants.